$$28 \text{ mi/gal} \times \frac{1.609 \text{ km}}{1 \text{ mi}} \times \frac{1 \text{ gal}}{3.785 \text{ L}} = 11.9 \text{ km/L}$$

$$\frac{2.54 \text{ cm}}{1 \text{ in}}$$

Question 1

Which of the following is the correct SI base unit for measuring the amount of substance?

Accepted Answer

mole (mol)

Question 2

A laboratory thermometer reads 42°C. What is this temperature in Kelvin?

Accepted Answer

$$K = 42 + 273.15 = 315.15$$

Question 3

Which of the following measurements is the most precise?

Accepted Answer

5.000 g

Question 4

A student measures the mass of a penny as 2.51 g. Which type of number is this?

Accepted Answer

An inexact number

Question 5

Which of the following represents a derived SI unit?

Accepted Answer

cubic meter $$(m^3)$$

Question 6

A sample of mercury has a mass of $$1.00 	imes 10^2$ g and occupies a volume of 7.36$ cm^3$. What is the density of mercury?

Accepted Answer

$$13.6 g/cm$^3$$

Question 7

Which of the following is NOT a correct statement about significant figures?

Accepted Answer

All zeros in a number are always significant.

Question 8

A car travels 28 miles per gallon of gasoline. How many kilometers per liter does it travel? (1 mile = 1.609 km, 1 gallon = 3.785 L)

Accepted Answer

$$28 	ext{ mi/gal} 	imes \frac{1.609 	ext{ km}}{1 	ext{ mi}} 	imes \frac{1 	ext{ gal}}{3.785 	ext{ L}} = 11.9 	ext{ km/L}$$

Question 9

Which of the following is an example of an exothermic process?

Accepted Answer

Starting an internal combustion engine

Question 10

A student adds $$2.345 g$$, $$0.07 g$$, and $$2.9975 g. $$What is the sum, rounded to the correct number of decimal places?

Accepted Answer

$$5.41 g$$

Question 11

Which of the following is the correct relationship for converting Celsius to Fahrenheit?

Accepted Answer

$$^\circ F = \frac{9}{5}(^\circ C) + 32$$

Question 12

A 125 mL sample of a liquid has a density of $$0.655 g/mL. $$What is its mass?

Accepted Answer

$$81.9 g$$

Question 13

Which of the following is a correct statement about the law of conservation of energy?

Accepted Answer

Energy can be neither created nor destroyed, only transferred or transformed.

Question 14

How many significant figures are in the measured quantity $$0.082060$$?

Accepted Answer

5

Question 15

Which of the following is an inexact quantity?

Accepted Answer

The mass of a penny

Question 16

A student multiplies $$7.1 m by$$ $$6.03 m. $$What is the answer, rounded to the correct number of significant figures?

Accepted Answer

$$43$$ $$m^2$$

Question 17

Which of the following is the correct SI unit for energy?

Accepted Answer

joule (J)

Question 18

A sample of ethanol has a density of $$0.798 g/mL. $$What volume is needed for $$15.0 g of $$ethanol?

Accepted Answer

$$11.8 mL$$

Question 19

Which of the following is a correct conversion factor for converting inches to centimeters?

Accepted Answer

$$\frac{2.54 	ext{ cm}}{1 	ext{ in}}$$

Question 20

Which of the following best describes the difference between mass and weight?

Accepted Answer

Mass is the amount of matter, weight is the force exerted by gravity on that matter.

Units, Measurement, and Problem Solving: Foundations of General Chemistry

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